Process for the manufacture, by spinning, of hollow or solid parts, more particularly of ferrous alloy



G. BODINAUX 2,748,465 MANUFACTURE, BY SPINNING, OF HOLLOW OR MORE PARTICULARLY OF FERROUS ALLOY June 5, 1956 PROCESS FOR THE SOLID PARTS,

Filed Sept. 30, 1952 Gusto)? Boclinaux, INVEWTOR PM KQ ATTQR/VEYJ United States Patent C PROCESS FOR THE MANUFACTURE, BY SPIN- NING, OF HOLL'GW R SOLID PARTS, MORE PARTICULARLY 0F FERROUS ALLOY Gaston Bodinaux, Liege, Belgium, assignor to Socictc Anonyme les Forges tie Zeebrugge, Herstal, Belgium Application September 30, 1952, Serial No. 312,367

Claims priority, application Belgium December 4, 1951 6 Claims. (Cl. 29-535) The invention has for object a new process providing for the manufacture, by spinning, of parts or articles of an kinds, whether solid or hcillo'w. In the latter case they may be made with or without .ends. The outer profil'e of the part may be similar or different from its inner profile. Likewise, the part may comprise two portions, one of which is hollow and the other solid, or the two portions are solid or hollow, having similar or different profiles and dimensions.

This process has essentially for object to permit the industrial manufacture of such parts by making use of quick and relatively cheap apparatus.

In numerous applications the process permits of produc'ing, without the subsequent application of thermal treatment, of parts having, in their mass, difierent mechanical characteristics. This variation may be previously determined with great accuracy.

From the foregoing it results that the process forming the subject of the invention is particularly advantageous in that it permits the normal use of the known spinning process for the treatment of ferrous alloys and, in ,particular, of steel. The results of this process are, therefore, at the same time, of a technical and economical nature, since it extends, in remarkable proportions, the range of industrial uses of spinning processes.

It is known that numerous parts, and, in particular,

parts with or without an end, are subsequently stressed and in particular steel, by reason of their inherent qualities and in some cases their cost, :could be very advantageously used.

The process forming the subject of the invention is preferably used .in conjunction with :the known spinning process, in such conditions that, not only the ferrous .alloys and, in particular, steel, become usable in all cases where such alloys are of advantage, but the spinning process itself becomes industrially applicable systematically to the said ferrous alloys :for the quick and relatively cheap manufacture of parts or articles of all kinds having, in their mass, variations in mechanical characteristics.

The process forming the :subject of the invention consists substantially :in produicng, preferably by spinning, a rough shaped part the walls of which have locally excesses of material, proportional to the increases in the mechanical characteristics of the finished part at right angles with the said excesses of material, then in bringice ing the said walls, by local compression of the material, into the shape and to the exact dimensions of those of the parts to be produced. The rough shaped part will generally be made by spinning, starting from a bar, the

latter itself being generally obtained by cutting it from a simple bar of suitable diameter. The rough shaped :part may be made in one or more spinning operations and it will have, in general, a shape and dimensions approximately similar to the final part to be produced.

The dimensions of the walls will be slightly greater than the final dimensions at right angles with the zones in which the mechanical characteristics must, rafter making the part, be greater than the inherent mechanical characteristics of the portions of the part which are to be the least stressed. These increases in thickness will be proportional or approximately proportional to the increases in the said mechanical characteristics.

The part is brought into its correct shape and dimensions by the stressing means, so that the excess thickness of material is compressed in such conditions that an actual molecular interpenetration is produced bringing about in particular an increase in hardnes which is prac tically, within limits, proportional to the ratio between the initial and the final dimensions, or again in the ratio of the dimensions of the rough shaped .part of those of the finished part.

The starting bar may be used as such, or after having undergone some modification in shape or in dimensions bymech'anical means or in any other manner.

In a preferred constructional form of the method according to the invention, the parts are produced in two separate stages which may be carried out in the course of a single operation or in two successive opera- .tions. Starting for example from a steel bar obtained by cutting it from a part of suitable diameter, the first stage consists in producing the rough shaped part by a spinning operation of any suitable type well known in the art. This rough shaped part has approximately .the shape and the dimensions of the .final part to be produced. It has extra thicknesses, which may be progressive or .not, at those places where the part to be produced is to have stronger mechanical characteristics than those of the rough shaped part produced by spinning.

The second stage of the process consists in subjecting the said rough shapedpart to at least one operation such that at right angles with all the extra thicknesses it is subjected to the action of compression, in such a way that the material undergoes a local crushing, the limits of this crushing being determined by molecular interpenetration such that all the parts of the .rough shaped part are brought to the exact dimensions of the final part to be produced. This second stage may be :eitected in the course of the first operation, in which case the latter is carried out, in two steps, but practically without interruption in the action on the material. In a more general manner, these two :steps will be carried out in two separate oper- .ations by means adapted respectively to form the rough shaped :part and to convert itinto the shapes and dimen sionsof the final pant.

The process can of :courseonly be carried out on one portion of the part, :for example one section, the other part or second section being either maintained in its initial shape and dimensions, :orract'ed nponin any suitable manner in order :to produce the changes in shape and dimensions necessary for producing the finished part.

The rough :shaped part produced by spinning may havellccalextra thicknesses which are, or are not progressive "and provided -intefiorlyor exteriorly of the part.

In some cases extra thicknesses may be provided at the same time both on the inner, and on the outer walls. The devices necessary for bringing the rough shaped part into the shape and dimensions of the finished part to be produced are therefore essentially variable, all these devices having nevertheless a common fundamental function, which consists in producing the local compression or crushing of the material.

The second stage of the process may be effected either in a single operation or in several successive operations.

In fact, all the material excesses present on a given part may be forced back into the mass, at the same time, by a single operation, or they may be treated individually or in predetermined groups.

Another method consists in stressing the same part partly internally and partly externally, all these means being determined by the particular shape of each part and especially the distribution in the mass of particular mechanical characteristics.

The method according to the invention is therefore of very general application.

The accompanying drawings illustrate, without any limiting effect, either of the parts shown or the means used for producing them, various parts which can be produced according to the invention. In the drawings,

Figures 1, 2 and 3 illustrate very diagrammatically the use of the method according to the invention for making a hollow part closed at one end, the excess material being disposed on the inner wall of the part;

Figures 4 to 7 illustrate very diagrammatically the use of the method for making a hollow part closed at one end, the excess material being disposed on the outer surface of the part;

Figure 8 illustrates very diagrammatically the use of the method for making a hollow part closed at one end, the excess material being disposed both on the inner and outer surfaces of the part;

Figures 9 and illustrate very diagrammatically the use of the method for making a hollow part closed at one end, the part having a complex shape;

Figures l1, l2 and 13 illustrate diagrammatically some embodiments produced by double spinning, and

Figures 14 and illustrate a hollow part open at both ends made according to the invention.

In the constructional example shown in Figures 1, 2 and 3, starting in the known manner, with a bar 1, there is produced by spinning a rough shaped part 2 approximating to the article to be produced but having an excess of material which is proportional to the increase in the mechanical characteristics which is to be subsequently produced by a mechanical operation. In this case, and as shown in Figure 2, the thickness of the cylindrical wall of the rough shaped part is progressively increased starting from a level A to the end or bottom 3. This rough shape is to be used for the production of a part the mechanical characteristics of which are to be increased proportionally starting from the said level A-A to the said end 3. This part 4 (Figure 3) is obtained, for example, by means of a punch 5, the part being held firmly in a die 6 in such a way that after the operation of the punch 5, the part 4 has its final shape and dimensions, the excess material having been compressed so that the cylindrical wall of the part 4 has, over its length, a variation in its mechanical characteristics in accordance with the diagram of Figure 3.

In the example shown in Figures 4 to 7, a similar result is produced, but in this example, the excess material is disposed on the outer surface of the part. As in the example of Figures 13, a rough shape 2 approximating to the shape of the finished article is produced by spinning from a bar 1, the cylindrical wall having an excess of material increasing progressively from a level A towards the end or bottom 3. In the rough shaped part, the hollow interior has its final shape and dimensions, but the excess material is, in this case, on the outer surface of the part, as shown in Figure 5.

In order to bring the rough shape into its final shape and dimensions, it is only necessary to support it interiorly -be produced by the process of the invention.

by the cylinder 7 and to move simultaneously the part 2 and the cylinder 7 through a die 3, for example by the thrust action of an external piston 9. As a result of the considerable pressure exerted at the same time by the piston 9 and the die 8 the rough shaped part 2 is brought to the shape and dimensions of the final part 4, as shown in Figure 7. In this finally shaped part, the mechanical characteristics will vary over its height or length in the manner shown in the diagram of Figure 7. The result is therefore similar to that produced in the embodiment first described.

It is of course possible, as illustrated as diagrammatically as possible in Figure 8, to produce a rough shape 2, by spinning, by starting from a bar or otherwise, in which the excess material is disposed at the same time both on the inner and outer surfaces. In this case, the dies and punches used for transforming the rough shape into the final part will be correspondingly shaped.

Obviously, increases in the mechanical characteristics may be produced in any part or parts of the finished article within limits duly and accurately predetermined. Thus, Figures 9 and 10 illustrate how, by the application of the method according to the invention, a complex part is produced in which not only the Wall but also the end or bottom are subjected to relatively considerable compression with a view to locally increasing the mechanical characteristics.

In this construction which could, for example, be used in the industrial manufacture of the pins of projectiles, a rough shaped part 2 is first of all made, in which the cylindrical wall has, towards the end, an excess of material 10 on its outer surface, and in which the end has also, in its annular part 11, a thickness which is substantially greater than the final thickness, as shown in Figure 9. In the final stage of the process, the rough shaped part 2 is supported interiorly by a punch 12, the shape and external dimensions of which are identical to those of the hollow interior of the part. The latter is forced through a die 8, for example, whilst the end is compressed between the punch 12 and a shaped underneath support 13 in such a way as to produce an annular boss 14. By reason of the latter, the end undergoes locally a reduction in thickness and, ipso facto, has imparted thereto a local increase in the mechanical characteristics. These simple means could also be generally applied to any kind of part, the punches and matrices or the dies, being, of course, adapted to the shape and to the dimensions of the parts to be made.

This same method can be used for making parts of very complex shape some embodiments of which are illustrated, simply by way of example, in Figures 11, 12 and other die or stamping methods, or by an extrustion or other method.

Figure 11 shows partly in radial section, a part 15 of complex shape the hollow interior 16 of which is very substantially different from the external shape of the part.

Solid masses may also be localised at any place considered suitable and the hollow interiors may have practically any shape.

Figure 12 illustrates a part in which a hollow portion 17 is joined to a solid portion 18; such parts can also easily Finally, solely with a view to demonstrating the complexity of the parts which can be produced, Figure 13 illustrates a bolt of very special shape in which the screw-threaded part 19 is extended by a cylindrical head 20 of bigger diameter, itself surmounted by a hollow head 21 of still bigger diameter, the hollow interior 22 being of complex shape.

In all these constructions, the rough shaped part and also the finished part, have an end which may, or may not be of regular shape.

It is obviously possible to use the same process for producing hollow parts having open ends. It is only necessary, in practice, to produce a rough shaped part with an end, as above described, the wall of which has, on its inner or outer surface, an excess or excesses of material proportional to the increase in the mechanical characteristics which it is desired to produce in the final phase of the process, or an excess or excesses of material corresponding to the interior and exterior profiles of the part. In this case the end is subsequently removed.

In the case of special parts having variable profiles, the part can be produced in a number of successive operations.

In the example of Figure 14 the starting material comprises a piece cut from a bar. The profile such as shown from X to Y is obtained by a first operation, and the profile Y to Z by the second operation. If necessary, these two successive operations could be arranged so as to obtain a similar part having an end at Y, as shown in Figure 15.

The method according to the invention, is applicable generally to all kinds of parts made from any material capable of being spun, but more especially, according to one feature of the invention, to the industrial manufacture of hollow parts having a bottom end, such for example as the pins and heads of projectiles.

This process provides considerable advantages both as regards cost and from technical considerations. First of all it permits the use of a raw material of relatively low cost price readily obtainable in the metallurgical market, in particular when starting from simple bars of ferrous alloy. This advantage is particularly appreciable during a time of mobilisation or armed conflict. The tools required, whilst being specially adapted, are nevertheless relatively simple and require a smaller capital investment when compared with the investment required by traditional processes.

These advantages result mainly from the fact that the power required is relatively small, compared with that required in other methods. The quality of the parts produced is exceptional, by reason of the basic principle and the rational flow of the metal. The fibres of this latter are correctly positioned and are protected against tearing and against all harmful stresses. On the other hand, the stresses characterising, in particular, the last phase of the method have for result to improve substantially the physical and mechanical characteristics of the metal at right angles with the parts stressed. Further, it is possible to maintain a good concentricity at the same time as providing for rapid manufacture of the parts, the result of which is to reduce the cost price thereof. A further advantage of the invention is that wastage of material is very substantially reduced resulting in an economy in material, which itself results in a further economy in the finishing operations since the removal of excess material involves additional cost. By reason of the precision and the appearance of the parts produced, the percentage of rejects and the magnitude of the subsequent finishing operations are reduced.

All these advantages make the method according to the invention a real advance in the technical means for manufacturing all parts, Whether solid or hollow, and with or without an end, and more especially parts of ferrous alloy, in particular of steel.

What I claim is:

1. A method of making hollow articles, particularly articles of ferrous alloys, said method comprising the steps of spinning a blank having side wall portions with excess of material proportional to the desired increase in mechanical resistance of said portions in the finished article and subjecting said blank to pressure of a matrix having the form of the outer surfaces of the finished article and of a punch having the form of the inner surfaces of the finished article while preventing the flow of said excess material, whereby side wall portions of the desired thickness of the finished article are formed by molecular copenetration of the material, said sidewall portions having greater mechanical resistance than other portions of the finished article.

2. A method of making hollow articles, particularly articles of ferrous alloys, said method comprising the steps of spinning .a blank having side wall portions with outwardly .and inwardly directed excess of material proportional to the desired increase in mechanical resistance of said portions in the finished article, and subjecting said blank to pressure of a matrix having the form of the outer surfaces of the finished article and of a punch having the form of the inner surfaces of the finished article while preventing the flow of said excess material, whereby side wall portions of the desired thickness of the finished article are formed by molecular copenetration of the material, said side wall portions having greater mechanical resistance than other portions of the finished article.

3. A method of making hollow articles, particularly articles of ferrous alloys, said method comprising the steps of spinning a bar to form a blank having side wall portions with excess of material proportional to the desired increase in mechancial resistance of said portions in the finished article, and subjecting said blank to pressure of a matrix having the form of the outer surfaces of the finished article and of a punch having the form of the inner surfaces of the finished article while preventing the flow of said excess material, whereby side wall portions of the desired thickness of the finished article are formed by molecular copenetration of the material, said side wall portions having greater mechanical resistance than other portions of the finished article.

4. A method of making hollow articles, particularly articles of ferrous alloys, said method comprising the steps of spinning a blank having substantially the form and dimensions of the finished article but having side wall portions with excess of material proportional to the desired increase in mechanical resistance of said portions in the finished article, and subjecting said blank to pressure of a matrix having the form of the outer surfaces of the finished article and of a punch having the form of the inner surfaces of the finished article while preventing the flow of said excess material, whereby side wall portions of the desired thickness of the finished article are formed by molecular copenetration of the material, said side wall portions having greater mechanical resistance than other portions of the finished article.

5. A method of making hollow articles, particularly articles of ferrous alloys, said method comprising the steps of spinning a blank having side wall portions with excess of material proportional to the desired increase in mechanical resistance of said portions in the finished article, and subjecting said blank to pressure of a fixed matrix having the form of the outer surfaces of thefinished article and of a movable punch having the form of the inner surfaces of the finished article while preventing the flow of said excess material, whereby side wall portions of the desired thickness of the finished article are formed by molecular copenetration of the material, said side wall portions having greater mechanical resistance than other portions of the finished article.

6. A method of making hollow articles, particularly articles of ferrous alloys, said method comprising the steps of spinning a blank having side wall portions with excess of material proportional to the desired increase in mechanical resistance of said portions in the finished article, and subjecting said blank to pressure of a movable matrix having the form of the outer surfaces of the finished article and of a fixed punch having the form of the inner surfaces of the finished article while preventing the flow of said excess material, whereby side wall portions of the desired thickness of the finished article are formed by molecular copenetration of the material, said side wall portions having greater mechanical resistance than other portions of the finished article.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Erhardt 'Apr. 11, 1893 Cayley Nov. 20, 1894 Schoen Oct. 31, 1905 Slick Jan. 13, 1914 McCann Apr. 3, 1934 

1. A METHOD OF MAKING HOLLOW ARTICLES, PARTICULARLY ARTICLES OF FERROUS ALLOYS, SAID METHOD COMPRISING THE STEPS OF SPINNING A BLANK HAVING SIDE WALL PORTIONS WITH EXCESS OF MATERIAL PROPORTIONAL TO THE DESIRED INCREASE IN MECHANICAL RESISTANCE OF SAID PORTIONS IN THE FINISHED ARTICLE AND SUBJECTING SAID BLANK TO PRESSURE OF A MATRIX HAVING THE FORM OF THE OUTER SURFACES OF THE FINISHED ARTICLES AND OF A PUNCH HAVING THE FORM OF THE INNER SURFACES OF THE FINISHED ARTICLE WHILE PREVENTING THE FLOW OF SAID EXCESS MATERIAL, WHEREBY SIDE WALL PORTIONS OF THE DESIRED THICKNESS OF THE FINISHED ARTICLE ARE FORMED BY MOLECULAR COPENETRATION OF THE MATERIAL, SAID SIDE WALL PORTIONS HAVING GREATER MECHANICAL RESISTANCE THAN OTHER PORTIONS OF THE FINISHED ARTICLE. 